A wonderfully effective little volume about the world's last frontier of mystery and darkness,- the great oceans, in which the author proves herself both scientist and stylist. While neither sensational nor sloppy with her facts, Miss Carson writes with clarity and controlled simplicity that makes her story available even to the uninitiated layman. She begins with the encompassing "mother sea" that once covered the whole earth, and from which the first forms of life evolved; she goes on to record briefly the changes of the great geological periods, the present characteristics of the seas, the tides, winds, currents. There are, too, chapters on isolated wonders such as the birth of volcanic islands. Chapters from this book were condensed into a profile of the sea for the New Yorker Miss Carson, who is also the author of has given us an exquisitely imaginative book, rooted in first rate scholarship, in a field that has not been over-explored.